The LCD (Liquid Crystal Display) possesses advantages of thin body, power saving and no radiation to be widely used in many application scope. It has been widely utilized in, such as mobile phones, PDAs (personal digital assistance), digital cameras, laptop screens or notebook screens.
The present thin film transistor liquid crystal display comprises a shell, a LCD panel located in the shell and a backlight module located in the shell. Particularly, the structure of the LCD panel mainly comprise a TFT Array Substrate (Thin Film Transistor Array Substrate), a CF (Color Filter) and a Liquid Crystal Layer. The working principle is that the light of backlight module is reflected to generate images by applying driving voltages to the two glass substrate for controlling the rotations of the liquid crystal molecules. The liquid crystal display mainly uses the color filter to show color images. The performance of the color filter directly affects the abilities of the color saturation, color contrast ratio, display brightness.
Please refer to FIG. 1, which is a top view diagram of a color filter according to prior art. The color filter comprises a substrate 100, and a color resist layer 200 and a black matrix 400 positioned on the substrate 100, and the color resist layer 200 comprises a plurality of color resist blocks 300 aligned in array. The color resist block 300 can be a red color resist block (R), a green resist block (G) or a blue resist block (B). The plurality of color resist blocks 300 are separated with the black matrix 400, and all the color resist blocks 300 utilize strip structure design. Each color resist block 300 corresponds to one sub pixel in the liquid crystal display. The color coordinate settings of the pixels of different colors can reflect the color expression capability of the liquid crystal display. The expressed colors of the pixels of different colors applied with the voltage will be restricted by the color expression capability of the color resist. For raising the color expression capability of the color resist, the visible light transmission of the pixel of the color may has loss, and thus, the entire display brightness of the liquid crystal display is decreased. At present, a method of adding white (W) matrix or yellow (Y) matrix to obtain RGBW or RGBY display matrix is proposed to achieve high brightness or high color saturation display modes. However, as increasing the color saturation, the display brightness of the display will be decreased. The requirement of the high color saturation and the high brightness cannot be satisfied at the same time.
The electrochromism means that the material occurs stable and reversible phenomenon in an electric field. When the material occurs the injection and extraction of the electrons and ions under the action of electrochemistry, the valence state and the chemical composition will be changed. Thus, the reflection and transmission capabilities of the material are changed. In the appearance and performance, it shows the reversible variation of the color and the transparency. The main properties are: (1), the injection and extraction of the charges in the electrochromic material can be conveniently realized with the variation of the external voltage or current. the volume of the injection or extraction charge determines the coloring degree; (2) coloring or non-coloring can be conveniently realized by changing the polarity of the voltage; (3) the colored material can keep in the colored state and have memory function in the condition that the current is cut and no oxydoreduction reaction occurs. Based on the aforesaid properties, the electrochromic material has been gradually employed to manufacture the display device.